package de.hs.rm;

import android.content.res.Resources;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;

public class ImageConverter {
	
	public static int calculateInSampleSize(
            BitmapFactory.Options options, int reqWidth, int reqHeight)
    {
	    // Raw height and width of image
	    final int height = options.outHeight;
	    final int width = options.outWidth;
	    int inSampleSize = 8;
	
	    if (height > reqHeight || width > reqWidth) {
	        if (width > height) {
	            inSampleSize = Math.round((float)height / (float)reqHeight);
	        } else {
	            inSampleSize = Math.round((float)width / (float)reqWidth);
	        }
	    }
	    return inSampleSize;
	}
    
    public static Bitmap decodeSampledBitmapFromResource(Resources res, int resId,
            int reqWidth, int reqHeight) {

        // First decode with inJustDecodeBounds=true to check dimensions
        final BitmapFactory.Options options = new BitmapFactory.Options();
        
        options.inJustDecodeBounds = true;
        BitmapFactory.decodeResource(res, resId, options);

        // Calculate inSampleSize
        options.inSampleSize = calculateInSampleSize(options, reqWidth, reqHeight);
        options.inPurgeable = true;

        // Decode bitmap with inSampleSize set
        options.inJustDecodeBounds = false;
        return BitmapFactory.decodeResource(res, resId, options);
    }

}
